Spring hinge



FIG. 1 is a top, front, right-side perspective view of a spring hingeshowing my new design;

FIG. 2 is a bottom, rear, left side perspective view thereof;

FIG. 3 is a front elevational view thereof, in an inverted position andfully extended; and,

FIG. 4 is a front elevational view thereof in its angular position.

The portions of the hinge that are not visible are not being claimed.

The ornamental design for a spring hinge, as shown and described.